What is the resolution of where the red fern grows

Billy calls his family, and they feel it is God's way of explaining to Billy why his dogs have died. Billy does feel better, and he says a final goodbye to his dogs. The family rides away and looks back at the red fern, visible in the distance.

The adult Billy reflects that he would like to revisit the Ozarks of his childhood. He would like to see his old haunts and landmarks. He is sure the red fern has grown and now covers his dogs' graves, for in his heart he believes "the legend of the sacred red fern."